Manitowoc Q series Ice Machine

[JerryG]

I've got a Manitowoc Q air cooled ice machine that they ran for two days without water. Now the water has been reconnected, however the machine won't start. It will go to wash ok. I checked the control board, and the relays don't close for the compressor or water pump, the led's don't light up, although the red led is very dim. I can run the compressor by holding in the contactor, and the condenser fan cycles, the high pressure switch is closed. The toggle switch does take the wire to the controller to ground when I operate the switch.
Any ideas? I tried to download a service manual from Manitowoc, but it won't start a download.

Thanks,
Jerry

[tsman]

check the ice flap magnet is making contact with bin switch

[JerryG]

Thanks, but where is the bin switch? There is a flapper at the top of the evaporator, but I thought that was to regulate ice sheet thickness.
The company that sold them the machine is out of business, and the supply house that I usually deal with is no longer a Manitowoc dealer. Naturally, they wanted this machine working today for a party they have, and it's really warm here today!

Thanks,

Jerry

[tsman]

the magnet is attached to a plastic flap attached to the evaporator coil the switch is usually on the left hand side .Have been to machines where flap is missing or been put on back to front so machine thinks its got a full bin.
this gives no light on pc board but allows for cleaning cycle to work.

[tsman]

the magnet is attached to a plastic flap attached to the evaporator coil the switch is usually on the right hand side .Have been to machines where flap is missing or been put on back to front so machine thinks its got a full bin.
this gives no light on pc board but allows for cleaning cycle to work.
see diagram part no 5

[JerryG]

Fantastic! Thanks very much. There is a flapper on the bottom of the evaporator, and I tried cycling it to see if the light would light, and it didn't, however, the woman at the facility told me that one of the guys there was playing in the bin before they called me. I'm going to stop over there tomorrow and check, I'm going to bet that you're right, and they put in on backwards.

I'll let you know how I make out, thanks again, and have a great day.

Jerry

[JerryG]

Here's an update. I got back this morning to look at this machine finally, and there was no magnet. Searching through the trough with a flashlight, I found it lying next to the pump. After I replaced it, it started right up and runs well. Now, however, after making a few sheets of ice, the red LED flashes. Toggling the switch per the directions, gives one flash. The machine does make ice, but apparently it takes too long? It seems to freeze for a while, then start to harvest too early, melting some of the cubes before they are fully formed. I cleaned up the thickness probe, and will watch it to see. Charge seems good, condenser coil and filter have been cleaned.

Ideas always welcome,
Thanks,
Jerry

[fridgey]

Hey Jerry,

One thing I've found with Manitowoc machines is the thickness probe can play up. They can seem to be working fine, then a couple of days later the machine breaks down again. I tend to replace them especially when the coating has worn away.

Another thing that never goes astray is, dismantling the water circulation system to clean it and running cleaning and sanatising chemicals through.

[JerryG]

Yes Sir, you're right! Apparently cleaning and adjusting the thickness probe did the trick, it's working fine now. I did clean the water system and run sanitizer, I wanted to ensure that the water flow was even across the face of the evaporator. This all started apparently, because they lost water flow to the unit for a few days, and then someone tried to 'fix' it for them. As I said, I normally do HVAC, but agreed to look at it for them, since its owned by a volunteer fire company.

Thanks for all the help!

Jerry